In recent years, an RFID (Radio Frequency Identification) system attracts attention and is introduced into, for example, a field of distributions. The RFID system includes an RF tag (also referred to as an “RFID tag”) including an IC chip and an antenna and being attached to a commodity and an RF tag reader and writer (hereinafter, simply also referred to as “reader and writer”) reading information stored in a memory in the IC chip of the RF tag in a contactless manner and writing information to the memory in the IC chip of the RF tag in a contactless manner.
An exemplary process in the RFID system is a batch information reading process (hereinafter, also referred to as “batch reading”) from plural RF tags in an inventory arrangement in a store. At this time, the reader and writer radiates electric waves over a range of several m and communicates with unspecified RF tags attached to plural commodities, whereby information stored in the RF tags is read all at once. Here, the RF tags as reading targets are generally arranged in a range spatially wider than a reading range of an antenna of the reader and writer. Accordingly, in the inventory arrangement, the information is acquired from the RF tags while moving the antenna of the reader and writer and changing a communication range.
Here, in the reader and writer according to the related art, a buzzer sounds when information can be acquired from an RF tag. A user can confirm whether the acquiring of information is successful depending on whether the buzzer sounds or not. Accordingly, in the inventory arrangement, the user goes around in a range of the inventory arrangement while checking whether the buzzer sounds and thus acquires information from the RF tags. Thereafter, the acquired information is compared with information which is stored in advance in a memory area of a server or the reader and writer and which is the same as the information stored in the RF tag in use (in a state where it is attached to a commodity), whereby it is checked whether any reading omission exists.
However, it is difficult for the user to accurately see the communication state or the reading omission only through the buzzer indicating that the reading is successful.